The Pacific Islands of Oceania are small islands and atolls occurring over a vast expanse of ocean that are characterized by immense biodiversity and endemism. This project represents a major expansion of the coverage of the Pacific Islands’ marine biodiversity on the IUCN Red List of Threatened Species. The threats to Pacific Island marine biodiversity are many. Results from IUCN Red List initiatives such as this can guide decision-making and conservation prioritization of Pacific Island governments, non-governmental organizations (NGOs) and the private sector. By shaping regional and national policies with these data in mind, priority sites for maintaining marine biodiversity can be identified and conserved.